Digester blow valve



March 1U, 1925. A 1,529,583

, J. D. EHRMANN ET Al.` v

DIGESTER BLow VALVE Filed Aug. 2, 1923 Patented Mar. l0, 19.25.

. UNITED STATES PATENT OFFICE.

JOHN D. EHRMANN, HARRY W. CLEVELAND AND DANIEL L. BELLINGER, OF WAUSAU,

WISCONSIN, ASSIGNORS TO D. J. MURRAY MANUFACTURING C0., OF WAUSAU, WIS- CONSIN, A CORPORATION OF WISCONSIN.

DIGESTER BLow VALVE.

Application filed August 2, 1923.

The present invention relates to improve' ments in digester blow valves used in paper mills and an object thereof is to provide an improvedvalve for this purpose which will be less expensive than the types now on the market, and which, on account of its improved design, will be much more durableH in service.

Another object ofthe invention is to dispense with the grooves 'and ribs or other guiding devices ordinarily placed at the two sides of the valve body, these ribs and grooves rapidly wearing and becoming troublesome, the .wear taking place rapidly on account of the combined chemical and abrasive action of the material passing through the valve at high velocity.

It is a further object of the invention to provide external means not subject to either abrasive or chemical action for preventing the valve stem from turning, the connection I between the stem and valve disc preventing the latter from turning.

It is a still further object of the invention to provide a valve with thickness of'metal proportionate to the wear which occurs in such valves at'diiferent points, and to so 4o design the valve, that the replacements, which must most frequently be made, namely the disc and the valve seat, can be done most expeditiously and at a minimum cost to the user.

`With the foregoing and other objects in view, the invention will be more fully described' hereinafter, and will be more particularly pointed out in the claims appended hereto.

In the drawings, wherein like symbols refer to like or corresponding parts throughout the several views, l Figure l is an end view of a digester blow valve constructed according to the invention.

Serial No. 655,308.

Figure 2 is a vertical section taken on the line 2 2 in Figure 1, and

Figure 3 is a horizontal section taken on the line 3 3 also in Figure 1.

Referring more particularly to the drawings 3 designates the valve body which is of acid resisting bronze material, and with-in thispvalve body, which is hollow and provided with an inlet and outlet 4 and 5 on the angle shown best in Figure 2 is a disc valve 6 adapted to close against a ring seat 7 removably carried upon a shoulder 8 extending annularly and in a substantially horizontal plane at an intermediate point between the inlet and the outlet. The disc valve is provided -with a face ring 9 embedded therein to take against the seating ring 7 in the closed position of the valve. Upon its upper side, the disc is provided with a usual form of socket l10 to receive the substantially rectangular foot 11 carried -by the lower end ofthe valve stem 12 whichfpasses up through a stuffing box 13 carried by the upper portion of the valve body and through a yoke 14 which is aiiixed upon the valve body. The upper portion of the valvek stem 12 is threaded to receivel a nut'15 carried in lthe upper part of the yoke and fixed to a gear wheel 16 which is rotated by the use of the pinion 17 meshing therewith and mounted upon a control shaft 18 journaled in appropriate bearings at the side of the yoke and parallel with the valve stem 12. A hand guide rib or Iiange 22 on the inside of the top yoke 14.

Inasmuch as the discs wear rapidly and have to be replaced several times during the life of the valve, provision must be made for removing them easily. It is also impracticable to use any steel or iron inside of the valve. The design of the rectangular foot in combination with the slotted part of the valve discenables the valve to be detached from the disc and access to the in-y terior of the valve body for this purpose is .1

permitted through a. removable door 25.

According to our invention we propose to cast upon the valve disc 6 vat a point adjacent the door 25 a small lug 26 which may be ground or filed to a small degree to enable it to clear the inside of the body casting. Thus'it will not interfere with the movement of the disc nor allow the disc to move out of place while it is being raised past the door opening. In the door 25 we provide a rib 27 which engages the small lug 26, thus giving the lug a bearing continuously durl ing 'the movement of the valve past the doo-r opening. l v

The bronze valve seats 7 have also to be replaced from time to time an'd we have adopted a further simple design in which the valve ring 7 engages the shoulder 8 by a drive fit. The ring is made as light and cheap as practicable. y The further advantage of this construction is that a long cold chisel may be inserted through the doorr opening and the seat ring 7 can be easily pried out, and the new one driven in place with a wooden bloclr or rawhide mallet. The door opening is placed low enough relatively to the valve seat so that this operation can be easily performed.

During the blowing operation, the velocity of the pulp through the valve is of course very high, and the steam pressure behind the pulp is of course highest when the disc is being raised but is only part way up. An appreciable length of time is required to open the valve fully and during the period in which the disc, to` some extent, opposes the flow of pulp, the latter is deiected against the opposite side of the valve body, on the discharge side of the seat, at very high velocity and in practice valves wear rapidly at this point. We therefore propose to increase the thickness at the points indicated by 28 andl 29 approximately 66 perlcgxiiit above Vthe thickness of the rest of the The unit construction of the valve body' rmits the use of a minimum amount of igh priced metal and a minimum amount of machine work in finishing.

The shaft 18 is either operated by hand modifications may be made in the details of construction and design of the above specifically described embodiment of this invention without departing from the spirit thereof, such changes and modifications being restricted on the s'cope of the following claims.

What is claimed is l. A digester blow valve comprising a valve bodyy having an inlet and outlet, a seat within said body, a valve mounted `Within said body'and moving toward and from said seat, a door located at a low point in the front part of the valve body and adjacent said seat, a rib on the inside of the door, and a lug projecting from the peripheral edge of said valve at the front part thereof, said lug adapted to .be engaged by the rib on said door.

y by

2. An improved digester blow valve coma seat ring detachably driven into saidshoulder, a valve disc of-acid resisting material in said body' adapted to seat a ainst said ring, a stem Jfor opening and osing said valve, cooperative means carried by the valve and stem for preventinY relative rotation thereof due to the flow o fluid through the valve, said disc further having a luv projecting from the forward part thereo a door in the front part of said valve body being located at a low elevation with respect to said Valve ring and having a rib u n the interior face of the door at substantlally an intermediate point, said rib adapted to engage said lug upon the disc, andmeans -to raise and lower said valve stem.

JOHN D. EHRMANN.

HARRY W. CLEVELAND; l y

DANIEL L. BELLINGER. 

